In this paper, we aim to examine those factors that are influential in the participation of Tehran University students in physical activities. According to the results and goals, this study is applied and descriptive respectively and based on the data collection this is a field study. A community sample of 16000 of Tehran University students participated in this study. Using Morgan table, 377 students were selected with random stratified selection procedure. To evaluate the effective factors in physical activity participation a researcher-made questionnaire with a reliability of 0.84 was administered. To analyze the data after the non-confirmation of parametric conditions and the natural data distribution using the Kolmogorov- Smirnov test, descriptive and deductive statistics including frequency and mean, Friedman test, Mann-Whitney test and Kruskal-Wallace test were used in SPSS with the significance of 0.05. The research findings have indicated that physical fitness, beauty and health have been more influential in physical activities and exercise participation than other factors. There was a significant difference in ranking the effective factors among male and female students. Gender, age and marital status were also among those factors contributing to the participation of students in exercises.